Hello,

I am currently planning my engine swap. I am going from the stock 305 TBI to a carbureted 350 that I built up. I do not want to have to splice up the wires for the ignition system, and I was wondering what my options are. I have all the stock ignition setup and it is running fine on the 305. I also have a MSD 6A, MSD billet distributor, and Blaster 2 coil that my I got out of another firebird (came with the 350). Could you let me know if any of these options are possible, and also if there are any better ones:

+Using stock ignition setup (stock distributor, coil, etc…)
+Using stock ignition setup but adding the 6A system
+Replacing the stock setup with the 6A, the MSD distributor, and the Blaster 2 coil

Keep in mind that I want to splice as few wires as possible. Any help and or suggestions would be much appreciated.

Thanks in advance,
Stephen

 

You need to replace the distributor. The stock distributor requires the ECM to provide timing information.

 

So does this mean that I would HAVE to go with the 3rd choice:

+Replacing the stock setup with the 6A, the MSD distributor, and the Blaster 2 coil

And this means cutting up a lot of wires, correct? Also are there any guides on this?

 

It would depend on the terminal arrangement on the MSD distributor, but there wouldn't be that much cutting involved.

 

The MSD distributor (pn 85551) has two wires coming off of it that connect into a single harness that plugs into the 6A.

Is there a guide that labels the wires that I will need to cut, I will need to cut the specific power lead and the tach lead, are there any more? And will this interfer with the VAC system?

 

would be covered under a TBI to carb swap guide?

 

It is not nessessary to "cut" any of the factory wireing to connect the MSD stuff.

The MSD needs a 12volt switched input. (turns it on and off only) Plug into your factory distributor connector (one of the leads will be 12 switched.

The MSDS need 12volts power from the battery (Big red wire). Run a new wire directly to the battery including a inline fuse.
The MSD needs to be grounded to the battery and to the engine block. Run new ground wires.
The tach lead from your factory distributor conecting plug goes to the tach output on th MSD.

None of these connections require you to cut the factory wireing. just attach spade leads to the factory plug ends on the relevent pin to get switched power and tach input.

 

Thanks a lot. Is there a guide that labels the wires (tach and the 12v switched)? Also where can the spade leads that plug into the harnesses be picked up?

 

Anyone know?

 

Spade terminals can be picked up at any parts store or hardware store. Check a wiring diagram and MSD's installation instructions to figure out which wire is which.

 

Thanks, I'll do. I think I might document this swap b/c there are not very many good guides out there.

For the fuel system, I read somewhere that I can keep the in tank electric pump, hook that to the mechanical one on the engine, and then use a return line to send the extra out (simplified version). I also saw one that used a vacuum controlled fuel pressure regulator. What is the best option?

 

Either of those solutions should work. You don't need to vacuum reference the fuel pressure regulator though, leaving it open to atmosphere is fine.